Just because someone is in care and funded by the State doesn’t mean they can’t buy gifts for their family at Christmas.
There are no specific guidelines about what is or is not allowed but the best approach is to apply common sense. Gifts need to be proportionate to the individual’s overall wealth and part of a person’s usual behaviour - in other words something they have done previously.
Problems are likely to arise if the value is such that the gift could be viewed as a deliberate act of deprivation, made with the intent of reducing the funds available to support care costs. So, a £5,000 gift to buy a care for a grandson may well create questions but £50 gift voucher is unlikely to create difficulty.